In Schedules API, "time_zone" has data like "London", "Hawaii", "Osaka".
The names are not in the database of timezone, https://www.iana.org/time-zones .
How can we found the definition of these time_zone?
Schedules API
https://developer.zendesk.com/api-reference/ticketing/ticket-management/schedules/#json-format

I can verify that your assumption is correct, we pull this list from the TimeZone class of RoR.
Thanks!